An optical imaging system can convert a paper document into a digital image. However, when a book is imaged by a non-contact imaging apparatus, for example, a overhead scanner or digital camera and etc., the pages of the book are often pressed by fingers so as to be fixed. In this case, there are fingers on both sides of the image as obtained, and the readability, integrity, and aesthetic property are reduced. FIG. 5 is a schematic view in which the pages of a book are pressed by fingers, and FIG. 6 is an image of a page as obtained by imaging, wherein it is apparent that the readability, integrity, and aesthetic property of the image are influenced by fingers on both sides of the book. Therefore, if the finger region can be removed by processing the image and filled by content of the page of the book, the quality of the image will be improved. Image inpainting is a technique for repairing image, which can remove a specified region in an image while making the change undiscoverable and was initially used for recovering the damaged oil painting.
Researchers proposed many methods for inpainting image, including structure based propagation, texture synthesis and example synthesis and so on. Some of these methods can be directly applied to remove finger region, and achieve good effects. However, the operation is time consuming and thus impractical.
Therefore, there is need for a method for inpainting image which can remove finger from the image of document while guarantee the change undiscoverable.